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1.
Front Psychiatry ; 11: 345, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32612545

RESUMO

Childhood sexual abuse is associated with significant subsequent pathology and neurodevelopmental disruption. In particular, childhood sexual abuse has been associated with heightened threat sensitivity. However, little work has directly investigated this issue. In this study, we examine the association of childhood sexual abuse to neural and behavioral responses to looming, threatening face stimuli. The study involved 23 adolescents with significant past sexual abuse and 24 comparison individuals matched on IQ, age, and sex. Participants were scanned during a looming threat task that involved negative and neutral, human faces and animals that appeared to either loom toward or recede from the participant. We found that adolescents who had been previously subjected to sexual abuse, relative to comparison adolescents, showed increased neural responses to threatening looming stimuli in regions including rostral and superior frontal gyrus as well as posterior cingulate gyrus. In addition, they were significantly more slowed by looming stimuli, particularly if these were human faces, than adolescents who had not been exposed. These data demonstrate that prior sexual abuse was associated with heightened neural responsiveness to looming threats in a series of regions beyond the amygdala. These data are interpreted within models of rostromedial frontal and posterior cingulate cortices that stress their role in self-referential emotional processing and emotional maintenance.

2.
Hum Brain Mapp ; 2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-32596977

RESUMO

The ENIGMA group on Generalized Anxiety Disorder (ENIGMA-Anxiety/GAD) is part of a broader effort to investigate anxiety disorders using imaging and genetic data across multiple sites worldwide. The group is actively conducting a mega-analysis of a large number of brain structural scans. In this process, the group was confronted with many methodological challenges related to study planning and implementation, between-country transfer of subject-level data, quality control of a considerable amount of imaging data, and choices related to statistical methods and efficient use of resources. This report summarizes the background information and rationale for the various methodological decisions, as well as the approach taken to implement them. The goal is to document the approach and help guide other research groups working with large brain imaging data sets as they develop their own analytic pipelines for mega-analyses.

3.
J Am Acad Child Adolesc Psychiatry ; 59(2): 263-273, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31026574

RESUMO

OBJECTIVE: Conduct disorder (CD) is a serious neurodevelopmental disorder marked by notably higher prevalence rates for boys than girls. Converging evidence suggests that CD is associated with impairments in emotion recognition, learning, and regulation. However, it is not known whether there are sex differences in the relationship between CD and emotion dysfunction. Prior studies on emotion functioning in CD have so far been underpowered for investigating sex differences. Therefore, our primary aim was to characterize emotion processing skills in a large sample of girls and boys with CD compared to typically developing controls (TDCs) using a comprehensive neuropsychological test battery. METHOD: We included 542 youths with CD (317 girls) and 710 TDCs (479 girls), 9 to 18 years of age, from a European multisite study (FemNAT-CD). Participants completed three experimental tasks assessing emotion recognition, learning, and regulation, respectively. Data were analyzed to test for effects of group and sex, and group-by-sex interactions, while controlling for potentially confounding factors. RESULTS: Relative to TDCs, youths with CD showed impaired emotion recognition (that was related to more physical and proactive aggression, and higher CU traits), emotional learning (specifically from punishment), and emotion regulation. Boys and girls with CD, however, displayed similar impairments in emotion processing. CONCLUSION: This study provides compelling evidence for a relationship between CD and deficient neurocognitive functioning across three emotional domains that have previously been linked to CD etiology. However, there was no support for sex-specific profiles of emotion dysfunction, suggesting that current neurocognitive models of CD apply equally to both sexes.

4.
Eur J Neurosci ; 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31738835

RESUMO

Patients with anxiety disorders suffer from impaired concentration, potentially as a result of stronger emotional interference on attention. Studies using behavioural measures provide conflicting support for this hypothesis. Elevated state anxiety may be necessary to reliably document differences in emotional interference in patients versus healthy controls. The present study examines the effect of experimentally induced state anxiety (threat-of-shock) on attention interference by emotional stimuli. Anxiety patients (n = 36) and healthy controls (n = 32) completed a modified affective Stroop task during periods of safety and threat-of-shock. Results indicated that in both patients and controls, threat decreased negative, but not positive or neutral, emotional interference on attention (both p < .001). This finding supports a threat-related narrowing of attention whereby a certain level of anxiety decreases task-irrelevant processing.

5.
J Affect Disord ; 253: 343-351, 2019 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-31078834

RESUMO

BACKGROUND: Attentional disruptions are common in PTSD, but findings across neuropsychological and neuroimaging studies have been variable. Few PTSD studies have investigated abnormalities in attention networks using a multi-modal imaging approach and attentional tasks that include emotionally-salient images. This study combined a behavioral task that included these images (emotional Stroop) with functional and structural neuroimaging (fMRI and diffusion tensor imaging; DTI) methods to comprehensively investigate attentional control abnormalities in a highly-traumatized civilian sample. METHODS: 48 traumatized women with and without PTSD received clinical assessments, fMRI and DTI. During fMRI, the Affective Stroop (AS), an attentional control task that includes emotionally-salient distractor images (trauma-relevant, positive, neutral) and variable task demands, was administered. RESULTS: In response to more difficult AS trials, participants with PTSD demonstrated lower activation in the dorsal and rostral anterior cingulate cortex and greater activation in the insula. This group also showed comparatively poorer performance on positive AS distractor trials, even after adjusting for trauma exposure. Performance on these trials inversely correlated with structural integrity of the cingulum bundle and uncinate fasciculus. CONCLUSIONS: Even after adjusting for trauma exposure, participants with PTSD showed worse performance on an attentional control task in the context of emotional stimuli. They also showed relatively lower cognitive control network activation and greater salience network activation. Fronto-parietal and fronto-limbic white matter connectivity corresponded with AS performance. Our findings indicate that attentional control impairments in PTSD are most evident in the context of emotional cues, and are related to decrements in function and structure of cognitive control and salience networks.


Assuntos
Atenção/fisiologia , Encéfalo/fisiopatologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Substância Branca/fisiopatologia , Adulto , Encéfalo/diagnóstico por imagem , Estudos de Casos e Controles , Imagem de Tensor de Difusão , Emoções/fisiologia , Feminino , Giro do Cíngulo/fisiopatologia , Humanos , Imagem por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Valores de Referência , Adulto Jovem
6.
Psychiatry Res Neuroimaging ; 278: 7-12, 2018 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-29935441

RESUMO

Individuals with posttraumatic stress disorder (PTSD) show deficits in recruiting neural regions associated with cognitive control. In contrast, trauma exposed individuals (TEIs) show increased recruitment of these regions. While many individuals who experience a trauma exhibit some PTSD symptoms, relatively few develop PTSD. Despite this, no work has examined the relationship between changes in PTSD symptoms and changes in neural functioning in TEIs longitudinally. This study examined the neural correlates of changing PTSD symptom levels in TEIs. Twenty-one military service members completed the affective stroop task while undergoing fMRI within 2 months of returning from deployment and a second scan 6-12 months later. Participants with PTSD or depression at baseline were excluded. PTSD symptom improvement was associated with greater increase in response to incongruent relative to congruent negative stimuli in dorsal anterior cingulate cortex and inferior frontal gyrus/anterior insula and increased BOLD response over time to emotional relative to neutral stimuli in inferior parietal cortex. Improvement in PTSD symptoms were not associated with changes in amygdala responsiveness to emotional stimuli. In short, the current data indicate that TEIs who become more able to recruit regions implicated in cognitive control show greater reductions in PTSD symptom levels.


Assuntos
Emoções/fisiologia , Militares/psicologia , Doenças Profissionais/fisiopatologia , Recrutamento Neurofisiológico/fisiologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/fisiopatologia , Cognição/fisiologia , Feminino , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/fisiopatologia , Humanos , Estudos Longitudinais , Imagem por Ressonância Magnética , Masculino , Doenças Profissionais/diagnóstico por imagem , Doenças Profissionais/psicologia , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiopatologia , Índice de Gravidade de Doença , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Transtornos de Estresse Pós-Traumáticos/psicologia , Teste de Stroop , Adulto Jovem
7.
J Abnorm Child Psychol ; 46(4): 741-754, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28776147

RESUMO

Theoretical models have implicated amygdala dysfunction in the development of Disruptive Behavior Disorders (DBDs; Conduct Disorder/Oppositional Defiant Disorder). Amygdala dysfunction impacts valence evaluation/response selection and emotion attention in youth with DBDs, particularly in those with elevated callous-unemotional (CU) traits. However, amygdala responsiveness during social cognition and the responsiveness of the acute threat circuitry (amygdala/periaqueductal gray) in youth with DBDs have been less well-examined, particularly with reference to CU traits. 31 youth with DBDs and 27 typically developing youth (IQ, age and gender-matched) completed a threat paradigm during fMRI where animate and inanimate, threatening and neutral stimuli appeared to loom towards or recede from participants. Reduced responsiveness to threat variables, including visual threats and encroaching stimuli, was observed within acute threat circuitry and temporal, lateral frontal and parietal cortices in youth with DBDs. This reduced responsiveness, at least with respect to the looming variable, was modulated by CU traits. Reduced responsiveness to animacy information was also observed within temporal, lateral frontal and parietal cortices, but not within amygdala. Reduced responsiveness to animacy information as a function of CU traits was observed in PCC, though not within the amygdala. Reduced threat responsiveness may contribute to risk taking and impulsivity in youth with DBDs, particularly those with high levels of CU traits. Future work will need to examine the degree to which this reduced response to animacy is independent of amygdala dysfunction in youth with DBDs and what role PCC might play in the dysfunctional social cognition observed in youth with high levels of CU traits.


Assuntos
Tonsila do Cerebelo/diagnóstico por imagem , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/diagnóstico por imagem , Transtorno da Conduta/diagnóstico por imagem , Adolescente , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/psicologia , Criança , Transtorno da Conduta/psicologia , Emoções/fisiologia , Humanos , Imagem por Ressonância Magnética , Masculino
8.
Am J Psychiatry ; 174(2): 110-117, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27631963

RESUMO

OBJECTIVE: Deficits in reinforcement-based decision making have been reported in generalized anxiety disorder. However, the pathophysiology of these deficits is largely unknown; published studies have mainly examined adolescents, and the integrity of core functional processes underpinning decision making remains undetermined. In particular, it is unclear whether the representation of reinforcement prediction error (PE) (the difference between received and expected reinforcement) is disrupted in generalized anxiety disorder. This study addresses these issues in adults with the disorder. METHOD: Forty-six unmedicated individuals with generalized anxiety disorder and 32 healthy comparison subjects group-matched on IQ, gender, and age performed a passive avoidance task while undergoing functional MRI. Data analyses were performed using a computational modeling approach. RESULTS: Behaviorally, individuals with generalized anxiety disorder showed impaired reinforcement-based decision making. Imaging results revealed that during feedback, individuals with generalized anxiety disorder relative to healthy subjects showed a reduced correlation between PE and activity within the ventromedial prefrontal cortex, ventral striatum, and other structures implicated in decision making. In addition, individuals with generalized anxiety disorder relative to healthy participants showed a reduced correlation between punishment PEs, but not reward PEs, and activity within the left and right lentiform nucleus/putamen. CONCLUSIONS: This is the first study to identify computational impairments during decision making in generalized anxiety disorder. PE signaling is significantly disrupted in individuals with the disorder and may lead to their decision-making deficits and excessive worry about everyday problems by disrupting the online updating ("reality check") of the current relationship between the expected values of current response options and the actual received rewards and punishments.


Assuntos
Transtornos de Ansiedade/fisiopatologia , Transtornos de Ansiedade/psicologia , Aprendizagem da Esquiva/fisiologia , Tomada de Decisões/fisiologia , Imagem por Ressonância Magnética , Córtex Pré-Frontal/fisiologia , Reforço Psicológico , Enquadramento Psicológico , Adolescente , Adulto , Transtornos de Ansiedade/diagnóstico , Feminino , Humanos , Aumento da Imagem , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Modelagem Computacional Específica para o Paciente , Reconhecimento Visual de Modelos/fisiologia , Valores de Referência , Adulto Jovem
10.
J Child Psychol Psychiatry ; 57(8): 938-46, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27062170

RESUMO

BACKGROUND: Previous work has shown that patients with conduct problems (CP) show impairments in reinforcement-based decision-making. However, studies with patients have not previously demonstrated any relationships between impairment in any of the neurocomputations underpinning reinforcement-based decision-making and specific symptom sets [e.g. level of CP and/or callous-unemotional (CU) traits]. METHODS: Seventy-two youths [20 female, mean age = 13.81 (SD = 2.14), mean IQ = 102.34 (SD = 10.99)] from a residential treatment program and the community completed a passive avoidance task while undergoing functional MRI. RESULTS: Greater levels of CP were associated with poorer task performance. Reduced representation of expected values (EV) when making avoidance responses within bilateral anterior insula cortex/inferior frontal gyrus (AIC/iFG) and striatum was associated with greater levels of CP but not CU traits. CONCLUSIONS: The current data indicate that difficulties in the use of value information to motivate decisions to avoid suboptimal choices are associated with increased levels of CP (though not severity of CU traits). Moreover, they account for the behavioral deficits observed during reinforcement-based decision-making in youth with CP. In short, an individual's relative failure to utilize value information within AIC/iFG to avoid bad choices is associated with elevated levels of CP.


Assuntos
Córtex Cerebral/fisiopatologia , Transtorno da Conduta/fisiopatologia , Tomada de Decisões/fisiologia , Neostriado/fisiopatologia , Desempenho Psicomotor/fisiologia , Reforço Psicológico , Adolescente , Criança , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino
11.
Data Brief ; 7: 66-70, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26955650

RESUMO

The neural circuitry underlying response control is often studied using go/no-go tasks, in which participants are required to respond as fast as possible to go cues and withhold from responding to no-go stimuli. In the current task, response control was studied using a fully counterbalanced design in which blocks with a low frequency of no-go cues (75% go, 25% no-go) were alternated with blocks with a low frequency of go cues (25% go, 75% no-go); see also "Segregating attention from response control when performing a motor inhibition task: Segregating attention from response control" [1]. We applied a whole brain corrected, paired t-test to the data assessing for regions differentially activated by low frequency no-go cues relative to high frequency go cues. In addition, we conducted a generalized psychophysiological interaction analysis on the data using a right inferior frontal gyrus seed region. This region was identified through the BOLD response t-test and was chosen because right inferior gyrus is highly implicated in response inhibition.

12.
Neuroimage ; 126: 27-38, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26584863

RESUMO

Considerable work has demonstrated that inferior frontal gyrus (IFG), anterior insula cortex (AIC) and the supplementary motor area (SMA) are responsive during inhibitory control tasks. However, there is disagreement as to whether this relates to response selection/ inhibition or attentional processing. The current study investigates this by using a Go/No-go task with a factorial design. We observed that both left IFG and dorsal pre-SMA were responsive to no-go cues irrespective of cue frequency. This suggests a role for both in the inhibition of motor responses. Generalized psychophysiological interaction (gPPI) analyses suggest that inferior frontal gyrus may implement this function through interaction with basal ganglia and by suppressing the visual representation of cues associated with no-go responses. Anterior insula cortex and a more ventral portion of pre-SMA showed greater responsiveness to low frequency relative to higher frequency stimuli, irrespective of response type. This may reflect the hypothesized role of anterior insula cortex in marking low frequency items for additional processing (cf. Menon and Uddin, 2010). Consistent with this, the gPPI analysis revealed significantly greater anterior insula cortex connectivity with visual cortex in response to low relative to high frequency cues.


Assuntos
Atenção/fisiologia , Mapeamento Encefálico/métodos , Córtex Cerebral/fisiologia , Função Executiva/fisiologia , Inibição Psicológica , Atividade Motora/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Adulto Jovem
13.
Neuroimage Clin ; 7: 19-27, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25610763

RESUMO

BACKGROUND: Recent neuroimaging work suggests that increased amygdala responses to emotional stimuli and dysfunction within regions mediating top down attentional control (dorsomedial frontal, lateral frontal and parietal cortices) may be associated with the emergence of anxiety disorders, including posttraumatic stress disorder (PTSD). This report examines amygdala responsiveness to emotional stimuli and the recruitment of top down attention systems as a function of task demands in a population of U.S. military service members who had recently returned from combat deployment in Afghanistan/Iraq. Given current interest in dimensional aspects of pathophysiology, it is worthwhile examining patients who, while not meeting full PTSD criteria, show clinically significant functional impairment. METHODS: Fifty-seven participants with sub-threshold levels of PTSD symptoms completed the affective Stroop task while undergoing fMRI. Participants with PTSD or depression at baseline were excluded. RESULTS: Greater PTSD symptom severity scores were associated with increased amygdala activation to emotional, particularly positive, stimuli relative to neutral stimuli. Furthermore, greater PTSD symptom severity was associated with increased superior/middle frontal cortex response during task conditions relative to passive viewing conditions. In addition, greater PTSD symptom severity scores were associated with: (i) increased activation in the dorsolateral prefrontal, lateral frontal, inferior parietal cortices and dorsomedial frontal cortex/dorsal anterior cingulate cortex (dmFC/dACC) in response to emotional relative to neutral stimuli; and (ii) increased functional connectivity during emotional trials, particularly positive trials, relative to neutral trials between the right amygdala and dmFC/dACC, left caudate/anterior insula cortex, right lentiform nucleus/caudate, bilateral inferior parietal cortex and left middle temporal cortex. CONCLUSIONS: We suggest that these data may reflect two phenomena associated with increased PTSD symptomatology in combat-exposed, but PTSD negative, armed services members. First, these data indicate increased emotional responsiveness by: (i) the positive relationship between PTSD symptom severity and amygdala responsiveness to emotional relative to neutral stimuli; (ii) greater BOLD response as a function of PTSD symptom severity in regions implicated in emotion (striatum) and representation (occipital and temporal cortices) during emotional relative to neutral conditions; and (iii) increased connectivity between the amygdala and regions implicated in emotion (insula/caudate) and representation (middle temporal cortex) as a function of PTSD symptom severity during emotional relative to neutral trials. Second, these data indicate a greater need for the recruitment of regions implicated in top down attention as indicated by (i) greater BOLD response in superior/middle frontal gyrus as a function of PTSD symptom severity in task relative to view conditions; (ii) greater BOLD response in dmFC/dACC, lateral frontal and inferior parietal cortices as a function of PTSD symptom severity in emotional relative to neutral conditions and (iii) greater functional connectivity between the amygdala and inferior parietal cortex as a function of PTSD symptom severity during emotional relative to neutral conditions.


Assuntos
Atenção/fisiologia , Encéfalo/fisiopatologia , Emoções/fisiologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Adulto , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Teste de Stroop , Adulto Jovem
14.
Soc Cogn Affect Neurosci ; 10(4): 537-44, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24939872

RESUMO

Social referencing paradigms in humans and observational learning paradigms in animals suggest that emotional expressions are important for communicating valence. It has been proposed that these expressions initiate stimulus-reinforcement learning. Relatively little is known about the role of emotional expressions in reinforcement learning, particularly in the context of social referencing. In this study, we examined object valence learning in the context of a social referencing paradigm. Participants viewed objects and faces that turned toward the objects and displayed a fearful, happy or neutral reaction to them, while judging the gender of these faces. Notably, amygdala activation was larger when the expressions following an object were less expected. Moreover, when asked, participants were both more likely to want to approach, and showed stronger amygdala responses to, objects associated with happy relative to objects associated with fearful expressions. This suggests that the amygdala plays two roles in social referencing: (i) initiating learning regarding the valence of an object as a function of prediction errors to expressions displayed toward this object and (ii) orchestrating an emotional response to the object when value judgments are being made regarding this object.


Assuntos
Tonsila do Cerebelo/fisiologia , Emoções , Expressão Facial , Percepção Social , Adulto , Mapeamento Encefálico , Medo/psicologia , Feminino , Identidade de Gênero , Felicidade , Humanos , Julgamento , Aprendizagem/fisiologia , Imagem por Ressonância Magnética , Masculino , Estimulação Luminosa , Córtex Pré-Frontal/fisiologia , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia
15.
Front Hum Neurosci ; 8: 714, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25309390

RESUMO

The amygdala has been implicated in the processing of emotion and animacy information and to be responsive to novelty. However, the way in which these functions interact is poorly understood. Subjects (N = 30) viewed threatening or neutral images that could be either animate (facial expressions) or inanimate (objects) in the context of a dot probe task. The amygdala showed responses to both emotional and animacy information, but no emotion by stimulus-type interaction; i.e., emotional face and object stimuli, when matched for arousal and valence, generate comparable amygdala activity relative to neutral face and object stimuli. Additionally, a habituation effect was not seen in amygdala; however, increased amygdala activity was observed for incongruent relative to congruent negative trials in second vs. first exposures. Furthermore, medial fusiform gyrus showed increased response to inanimate stimuli, while superior temporal sulcus showed increased response to animate stimuli. Greater functional connectivity between bilateral amygdala and medial fusiform gyrus was observed to negative vs. neutral objects, but not to fearful vs. neutral faces. The current data suggest that the amygdala is responsive to animate and emotional stimuli. Additionally, these data suggest that the interaction between the various functions of the amygdala may need to be considered simultaneously to fully understand how they interact. Moreover, they suggest category-specific modulation of medial fusiform cortex as a function of emotion.

16.
Stud Health Technol Inform ; 199: 61-5, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24875691

RESUMO

Functional magnetic resonance imaging (fMRI) is helping us better understand the neurologic pathways involved in posttraumatic stress disorder (PTSD). We previously reported that military service members with PTSD after deployment to Iraq or Afghanistan demonstrated significant improvement, or normalization, in the fMRI-measured activation of the amygdala, prefrontal cortex and anterior cingulate gyrus following exposure therapy for PTSD. However, our original study design did not include repeat scans of control participants, rendering it difficult to discern how much of the observed normalization in brain activity is attributable to treatment, rather than merely a practice effect. Using the same Affective Stroop task paradigm, we now report on a larger sample of PTSD-positive combat veterans that we treated with exposure therapy, as well as a combat-exposed control group of service members who completed repeat scans at 3-4 month intervals. Findings from the treatment group are similar to our prior report. Combat controls showed no significant change on repeat scanning, indicating that the observed differences in the intervention group were in fact due to treatment. We continue to scan additional study participants, in order to determine whether virtual reality exposure therapy has a different impact on regional brain activation than other therapies for PTSD.


Assuntos
Encéfalo/fisiopatologia , Distúrbios de Guerra/reabilitação , Terapia Implosiva , Militares/psicologia , Transtornos de Estresse Pós-Traumáticos/reabilitação , Veteranos/psicologia , Guerra , Adulto , Distúrbios de Guerra/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Estados Unidos , Adulto Jovem
17.
Hum Brain Mapp ; 35(5): 2137-47, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23868733

RESUMO

OBJECTIVES: The neural correlates of human cooperative behavior remain poorly understood. Previous work has suggested that increases in striatal activation while punishing unfair offers represents reward signaling. However, other regions are also implicated when punishing others, for example dorsomedial frontal cortex (dmFC), anterior insula cortex (AIC), and periaqueductal gray (PAG). Moreover, the response of other regions implicated in signaling reward, for example ventromedial prefrontal cortex (vmPFC) or posterior cingulate cortex (PCC), has not been systematically examined. EXPERIMENTAL DESIGN: Functional magnetic resonance imaging utilizing parametric modulation was conducted on 21 healthy adults participating in a social exchange paradigm. PRINCIPAL OBSERVATIONS: Participants showed significant positive modulation of activity as a function of delivered punishment in caudate, dmFC, AIC, and PAG; that is, higher punishments by participants of unsatisfactory offers were associated with increasing activity within these regions. However, participants showed significant negative modulation of activity as a function of delivered punishment in vmPFC and PCC; increases in punishment level by participants were associated with decreases in activity within these regions. CONCLUSIONS: The current data question whether caudate activity when punishing unfair offers should be considered to indicate the reward value of this punishment. Instead, this activity, in conjunction with activity within dmFC, AIC, and PAG, may represent the organization of an untypical, punishing response that represents a reactive aggressive response to provocation. Notably, an inverse, regulatory relationship between vmPFC and PAG activity has been previously implicated in the context of another stimulus for reactive aggression; looming threat (Mobbs et al. [2007]: Science 317:1079-1083).


Assuntos
Agressão/fisiologia , Encéfalo/fisiologia , Princípios Morais , Punição , Recompensa , Adulto , Encéfalo/irrigação sanguínea , Feminino , Jogos Experimentais , Humanos , Processamento de Imagem Assistida por Computador , Modelos Lineares , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Adulto Jovem
18.
Neuroimage Clin ; 3: 531-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24371791

RESUMO

BACKGROUND: Many patients with Posttraumatic Stress Disorder (PTSD) feel overwhelmed in situations with high levels of sensory input, as in crowded situations with complex sensory characteristics. These difficulties might be related to subtle sensory processing deficits similar to those that have been found for sounds in electrophysiological studies. METHOD: Visual processing was investigated with functional magnetic resonance imaging in trauma-exposed participants with (N = 18) and without PTSD (N = 21) employing a picture-viewing task. RESULTS: Activity observed in response to visual scenes was lower in PTSD participants 1) in the ventral stream of the visual system, including striate and extrastriate, inferior temporal, and entorhinal cortices, and 2) in dorsal and ventral attention systems (P < 0.05, FWE-corrected). These effects could not be explained by the emotional salience of the pictures. CONCLUSIONS: Visual processing was substantially altered in PTSD in the ventral visual stream, a component of the visual system thought to be responsible for object property processing. Together with previous reports of subtle auditory deficits in PTSD, these findings provide strong support for potentially important sensory processing deficits, whose origins may be related to dysfunctional attention processes.

19.
Front Hum Neurosci ; 7: 46, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23450237

RESUMO

Self-referential processing is defined as the process by which a person becomes aware that specific contents are related to his or her own self. Cortical midline structures (CMS), such as dorsal and medial prefrontal cortex, and regions such as inferior frontal cortex, insula, and temporal pole have been implicated in self-referential processing. However, the specific contribution of each of these areas is still largely unknown. More particularly, not many studies have examined the influence of valence and decision making difficulty on regions involved in self-referential processing. In this study, participants evaluated how well personality traits, differing in valence and decision difficulty, described themselves or the current US President. In line with predictions, ventral, rostral, and dorsal parts of medial prefrontal cortex showed greater activity when participants judged traits about themselves relative to judging traits about the current US President. However, none of these regions showed significant modulation by trait valence. Increasing trait decision difficulty was associated with increased activity within dorsal medial prefrontal cortex and bilateral anterior insula. However, there was very minimal overlap (6/119 voxels, i.e., 5%) of the regions of dorsal medial prefrontal cortex implicated in self-referential processing and those implicated in trait decision difficulty. The results are interpreted within current accounts of self-referential processing.

20.
Biol Psychiatry ; 72(6): 476-82, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22592057

RESUMO

BACKGROUND: Generalized social phobia (GSP) and generalized anxiety disorder (GAD) are both associated with emotion dysregulation. Research implicates dorsal anterior cingulate cortex in both explicit emotion regulation (EER) and top-down attentional control (TAC). Although studies have examined these processes in GSP or GAD, no work compares findings across the two disorders or examines functioning in cases comorbid for both disorders (GSP/GAD). Here we compare the neural correlates of EER and TAC in GSP, GAD, and GSP/GAD. METHODS: Medication-free adults with GSP (EER n = 19; TAC n = 18), GAD (EER n = 17; TAC n = 17), GSP/GAD (EER n = 17; TAC n = 15), and no psychopathology (EER n = 18; TAC n = 18) participated. During EER, individuals alternatively viewed and upregulated and downregulated responses to emotional pictures. During TAC, they performed an emotional Stroop task. RESULTS: For both tasks, significant group × condition interactions emerged in dorsal anterior cingulate cortex and parietal cortices. Healthy adults showed significantly increased recruitment during emotion regulation, relative to emotion-picture viewing. GAD, GSP, and GSP/GAD subjects showed no such increases, with all groups differing from healthy adults but not from each other. Evidence of emotion-related disorder-specificity emerged in medial prefrontal cortex and amygdala. This disorder-specific responding varied as a function of emotion content but not emotion-regulatory demands. CONCLUSIONS: GSP and GAD both involve reduced capacity for engaging emotion-regulation brain networks, whether explicitly or via TAC. A reduced ability to recruit regions implicated in top-down attention might represent a general risk factor for anxiety disorders.


Assuntos
Transtornos de Ansiedade/fisiopatologia , Atenção/fisiologia , Emoções/fisiologia , Giro do Cíngulo/fisiopatologia , Transtornos Fóbicos/fisiopatologia , Adulto , Análise de Variância , Comorbidade , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Fatores de Risco , Teste de Stroop
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